Researches show that, in a related Long Term Evolution (LTE) system design, a resource utilization rate is relatively low, for example, an average resource utilization rate is 2%˜20%. For a system signal such as a synchronization signal, a system broadcast message and a common reference signal, no matter whether there is a user presently residing in a cell or whether there is a user required to send and receive data or not, the system signal is periodically sent or each frame is sent, which may make a difference between power consumption of base stations with a light load (for example, a resource utilization rate is 2%) and a heavy load (for example, a resource utilization rate is 20%) not so great, that is, most of the power consumption of the base stations is occupied by sending of the system signal. Therefore, it is necessary to further consider optimization of sending of the system signal during LTE.
In a related LTE system, a synchronization signal and a system broadcast message are periodically sent. In a radio frame, the synchronization signal is sent every 5 ms, a first system broadcast message such as a Master Information Block (MIB) is periodically sent on a Physical Broadcast Channel (PBCH) every 10 ms, and another system broadcast message such as System Information Block (SIB) information is periodically sent. After downlink synchronization, a terminal acquires PBCH information and an SIB to further obtain uplink access configuration information and then sends an uplink access request preamble signal, and even though there is no terminal required to send data and receive data in a cell, a system may still periodically send the synchronization signal and the system broadcast message, which undoubtedly brings system power consumption and resource loss. For LTE, an existing on/off mechanism for a small cell only prolongs a Discover Reference Signal (DRS) period and may not send a DRS according to a requirement, which may also bring system power consumption and system resource loss.
Along with development of a communication technology, a data service demand keeps increasing, but available low-frequency carriers become very scarce. Therefore, communication based on high-frequency (30˜300 GHz) carriers which have yet not been fully utilized becomes one of important communication means for future high-speed data communication. For high-frequency carrier-based communication, an available bandwidth is quite large, so that effective high-speed data communication may be provided. At the same time, high-frequency communication is also confronted with such a great technical challenge that a high-frequency communication signal, relative to a low-frequency signal, has great spatial fading and thus its outdoor communication quality is reduced. Because of wavelength reduction, more antennae may be used to perform beam-based communication to compensate spatial fading loss. But in such a manner, during high-frequency communication, a synchronization signal and a system message are sent to achieve a purpose of coverage and are required to be sent in each beam direction, and a manner of periodically sending the synchronization signal and a system broadcast message in a related technology undoubtedly increases system power consumption and system resources for sending the synchronization signal and the system message.